<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>svg</title>
  <style>
    #svg{
      background-color: gray;
    }
  </style>
</head>

<body>
  <svg id="svg" width="1200" height="500">
<line  x1="100" y1="100" x2="200" y2="200" stroke="yellowgreen"></line>
<polyline points="100 200 200 300 200" stroke="yellowgreen"></polyline>
  </svg>
</body>
</html>